My advice is get out of the hosting business, it's not worth the trouble at a small scale ;) There is always room for another hosting administration system, th

My advice is get out of the hosting business, it's not worth the trouble at a small scale ;) There is always room for another hosting administration system, though 7 to 10 months sounds pretty optimistic when considering the feature list you'll need to even be seen as competitive with cPanel. Webmin/Virtualmin seems like it has the ability to manage multiple VPSes, so that might be a more realistic target for comparison.